Mixing device



Sept. 10,1940. R. w. SCOTT 2,214,147

MIXING DEVICE Filed Feb. .11, 1938 IINVENTOR BY Rm [AK-SCOTT o wufl' n'li ATTORNEYS Patented Sept. 10, 1940 Ray W. Scott, Detroit, Mich assignor to Bendix Home Appliances, Inc., South Bend,'-In'd., a corporation of Delaware Application February 1 5 Claims.

cold fluids such as water to'maintain the mixtu.re at asubstantially. constant temperature. 5 One of the objects of the invention is to provide a mixing device in which-the fluid to be a mixed is controlled by..va1ves operated by fluid power devices which are supplied with actuating fluid under the control of means responsive to a function of the mixed fluid. Preferably one or more of the fluids to be mixed is utilized as'the actuating fluid for the power devices. Another object of the invention is to provide a mixing device having power. operated valves in which only one valve may be opened or all of the valves may be opened-simultaneously. If desired the power means may be provided with remotely operated controls. :Another object of the invention is to provide a mixingdevice for hot and cold fluids having fluid power operated valves in which the supply of actuating fluid to the power devices is automatically controlled in response to the temperature of the mixed fluids. Preferably the actuating fluid is supplied through a. flexible tube adapted to register more or less with spaced inlet ports to the power devices and moved by a bimetal thermostat responsive to the temperature of the mixed fluids.

of the invention will be apparent from the following description of the embodiment shown in the accompanying drawing, in which: Figure 1 is a central section through a mixing device embodying theinvention; and

Figure 2 isa section on the line 2-2 of Figure 1. Theillustrated mixing device is particularly adapted tomix hot and cold-water to obtain a mixture at a substantially constant temperature and comprises a.mixing.chamb er ill having an outlet pipe H2 at its bottom and a flat plate 64 closing its top. The plate l4 carries a head 56 formed with a cold water inlet i8 and a hot.

water inlet 20 communicating respectively .with

sources of hot and cold water. The inlet 18 and 2B communicate with" the mixing chamber through ports 22 and 24" respectively.

In order to control the proportions of hot and cold water,- valves 26 and '28 are provided controlling the ports 22 and. 24 respectively and The. dias phragms are carried by a block 34 supported from operated by diaphragms 3 and 32.

the plate I4 by bolts 36. A' pair of passages 38 and 40 are provided'in the block 84 communicatji ing with the diaphragms 30 and 32 respectively .Other objects, advantages and novel features 5 both valves 26 and 28 the same amount. "however, the temperature should be. higher or 1,- 1928, serial 189,967 (01. 236-42) This invention relates to mixing devices and 3 more particularly to devices for mixing hot' and and having spacedinlet' openings 42 and arranged side by sidesubstantially at the, center of the block.

"Actuating fluid for the diaphragms is sup-1 plied through a flexible tube 46 connected at its 5 upper end'to the inlet l8 and having a discharge nozzle 48 at its lower end adapted to discharge 1 water under pressure into the inlet openings 42 and 44. When the nozzle 48 is substantially, centered between the openings, both d iaphragms 10 will be subjected to equal pressure, b utas it is -moved more-nearly into register with one opening and out'of register with the other, the pres-- =sure under one diaphragm will increase, while .that under the other diaphragm decreases.

14$ The position of the nozzle 48 iscontrolled bya bimetal thermostatic strip 5}). 'securedat its upper end to the plate I4 and carrying a series 01 clamps 52 which connect it to the tube 46.

A-setting screw-54 maybe provided to adjust 20 the setting .of the strip'Sil. Admission of water to the tube 46 is controlled by a pilot valve 56 which is normally closed and adapted to be opened by a solenoid 5B. When the solenoid 58 is energized, water under pressure will flow from inlet [8 through the tube 46 and will be discharged .from the nozzle 48 into the inlet openings 42 and 44. This creates pressure below diaphragms 30 and 32 to open the valves 26 and 28, admitting both hot and cold 80 water to the. mixing chamber. If the temperature of the resultant mixture is that for which the-strip 50 is adjusted, the nozzle 48 will be centered between openings 42 and 44 to open lower than that desired, the nozzle, will be deflecteg toiop'en one of the valves further, thereby to increase the supply of either coldor hot water and decrease the supply of the other to bring the 4 temperature back to the desired value.

In order to openone of, the valves without 7 opening the other, separate means may be provided to conduct water to one only of thediaphra'gms. As shownpa pipe. 60 is connected to 5 j the inlet 20 and tea passage 62 leading'to the Y space below the diaphragm 32. The passage 6 is controlled bya pilot valve 64 operated .by, a solenoid 66.

- Whenthe valve it is opened by energization 60' If. 35 i vice, it will be apparent that it might be employed equally well to control the mixing'o'f any other desired fluids and that numerous other changes might be made therein. It is therefore not intended to limit the scope of the invention to the exactform shown, nor otherwise than by the terms of the appended claims.

What is claimed is: I

1. A mixing device comprising a mixing chamber, inlets for fluids to be mixed, valves controlling communication of said inlets with' the mixing chamber, fluid operated power means connected to each of said valves and having spaced inlet openings for operating fluid, a tube connected to one of said first named inlets and having a movable discharge end adapted to discharge fluid into said inlet openings, and means responsive to a function of the mixed fluids in the mixing chamber to move said discharge end to vary the relative pressure effects on the several inlet openings.

2. A mixing device for hot and cold fluids comprising a mixing chamber, hot and cold fluid inlets, a pair of normally closed valves controlling communication of said inlets respectively with the mixing chamber, individual fluid operated power means connected 'to each of said valves to open them, a tube to conduct fluid from one of said inlets to said power means, valve means to open and close said tube to open and close said first-named valves, and means responsive to the temperature of the mixed fluid in the mixing chamber to control communication of said tube with the power means respectively thereby to control the valves.

3. A mixing device for hot and cold fluids comprising a mixing chamber, hot and cold fluid inlets, a pair of valves controlling communication 01' said inlets respectively with the mixing chamber, fluid operated power means connected to each of said valves, a tube to conduct fluid from one or said inlets to said power means, means responsive to the temperature of the mixed fluid in the mixing chamber to control communication of said tube with the power means respectively thereby to control the valves, and a second tube connected to one of said inlets and to one only of the power means to open one onl of said ed to register with said inlet openings, and

thermostatic means responsive .to the temperature of the fluid in the mixing chamber to move said discharge end.

5. A mixing device for hot and cold fluids comprising a. mixing chamber, hot and cold fluid inlets, a pair of valves controlling communication of said inlets respectively with the mixing chamber, fluid operated power means connected to each of said valves, said power means having spaced fluid inlet openings-a flexible tube connected to one of said first named inlets and having a discharge end adapted to register with said inlet openings, and thermostatic means responsive to the temperature of the fluid in the mixing chamber to move said discharge end, said thermostatic means comprising a bimetal strip lying along and secured to said flexible tube. 

